The Sentences of Porphyry, that are a compendium of the Plotinus Enneads, include a review of the locus vexatus of the third century Platonism, which has its origin in the interpretation of a controversial passage of Timaeus, 39e. We will review the historical causes of Porphyry, under Longinus influence, and the controversy with Amelius and Plotinus on his arrival in Rome. His subsequent “retraction” takes him to accept that Intellect is identified with the multiplicity of intellections that intelligizes. Intellect is an intelligent subject and, at the same time, an intelligized object, that is, itself exerts on its own intellectual activity. Our analysis will seek to bring together texts of the Sentences, particularly from the 43, with excerpts from Plotinus treaties.